1/*
2*******************************************************************************
3*
4*   Copyright (C) 2003-2006, International Business Machines
5*   Corporation and others.  All Rights Reserved.
6*
7*******************************************************************************
8*   file name:  utrace.h
9*   encoding:   US-ASCII
10*   tab size:   8 (not used)
11*   indentation:4
12*
13*   created on: 2003aug06
14*   created by: Markus W. Scherer
15*
16*   Definitions for ICU tracing/logging.
17*
18*/
19
20#ifndef __UTRACE_H__
21#define __UTRACE_H__
22
23#include <stdarg.h>
24#include "unicode/utypes.h"
25
26/**
27 * \file
28 * \brief C API:  Definitions for ICU tracing/logging.
29 *
30 * This provides API for debugging the internals of ICU without the use of
31 * a traditional debugger.
32 *
33 * By default, tracing is disabled in ICU. If you need to debug ICU with
34 * tracing, please compile ICU with the --enable-tracing configure option.
35 */
36
37U_CDECL_BEGIN
38
39/**
40 * Trace severity levels.  Higher levels increase the verbosity of the trace output.
41 * @see utrace_setLevel
42 * @stable ICU 2.8
43 */
44typedef enum UTraceLevel {
45    /** Disable all tracing  @stable ICU 2.8*/
46    UTRACE_OFF=-1,
47    /** Trace error conditions only  @stable ICU 2.8*/
48    UTRACE_ERROR=0,
49    /** Trace errors and warnings  @stable ICU 2.8*/
50    UTRACE_WARNING=3,
51    /** Trace opens and closes of ICU services  @stable ICU 2.8*/
52    UTRACE_OPEN_CLOSE=5,
53    /** Trace an intermediate number of ICU operations  @stable ICU 2.8*/
54    UTRACE_INFO=7,
55    /** Trace the maximum number of ICU operations  @stable ICU 2.8*/
56    UTRACE_VERBOSE=9
57} UTraceLevel;
58
59/**
60 *  These are the ICU functions that will be traced when tracing is enabled.
61 *  @stable ICU 2.8
62 */
63typedef enum UTraceFunctionNumber {
64    UTRACE_FUNCTION_START=0,
65    UTRACE_U_INIT=UTRACE_FUNCTION_START,
66    UTRACE_U_CLEANUP,
67    UTRACE_FUNCTION_LIMIT,
68
69    UTRACE_CONVERSION_START=0x1000,
70    UTRACE_UCNV_OPEN=UTRACE_CONVERSION_START,
71    UTRACE_UCNV_OPEN_PACKAGE,
72    UTRACE_UCNV_OPEN_ALGORITHMIC,
73    UTRACE_UCNV_CLONE,
74    UTRACE_UCNV_CLOSE,
75    UTRACE_UCNV_FLUSH_CACHE,
76    UTRACE_UCNV_LOAD,
77    UTRACE_UCNV_UNLOAD,
78    UTRACE_CONVERSION_LIMIT,
79
80    UTRACE_COLLATION_START=0x2000,
81    UTRACE_UCOL_OPEN=UTRACE_COLLATION_START,
82    UTRACE_UCOL_CLOSE,
83    UTRACE_UCOL_STRCOLL,
84    UTRACE_UCOL_GET_SORTKEY,
85    UTRACE_UCOL_GETLOCALE,
86    UTRACE_UCOL_NEXTSORTKEYPART,
87    UTRACE_UCOL_STRCOLLITER,
88    UTRACE_UCOL_OPEN_FROM_SHORT_STRING,
89    UTRACE_COLLATION_LIMIT
90} UTraceFunctionNumber;
91
92/**
93 * Setter for the trace level.
94 * @param traceLevel A UTraceLevel value.
95 * @stable ICU 2.8
96 */
97U_STABLE void U_EXPORT2
98utrace_setLevel(int32_t traceLevel);
99
100/**
101 * Getter for the trace level.
102 * @return The UTraceLevel value being used by ICU.
103 * @stable ICU 2.8
104 */
105U_STABLE int32_t U_EXPORT2
106utrace_getLevel(void);
107
108/* Trace function pointers types  ----------------------------- */
109
110/**
111  *  Type signature for the trace function to be called when entering a function.
112  *  @param context value supplied at the time the trace functions are set.
113  *  @param fnNumber Enum value indicating the ICU function being entered.
114  *  @stable ICU 2.8
115  */
116typedef void U_CALLCONV
117UTraceEntry(const void *context, int32_t fnNumber);
118
119/**
120  *  Type signature for the trace function to be called when exiting from a function.
121  *  @param context value supplied at the time the trace functions are set.
122  *  @param fnNumber Enum value indicating the ICU function being exited.
123  *  @param fmt     A formatting string that describes the number and types
124  *                 of arguments included with the variable args.  The fmt
125  *                 string has the same form as the utrace_vformat format
126  *                 string.
127  *  @param args    A variable arguments list.  Contents are described by
128  *                 the fmt parameter.
129  *  @see   utrace_vformat
130  *  @stable ICU 2.8
131  */
132typedef void U_CALLCONV
133UTraceExit(const void *context, int32_t fnNumber,
134           const char *fmt, va_list args);
135
136/**
137  *  Type signature for the trace function to be called from within an ICU function
138  *  to display data or messages.
139  *  @param context  value supplied at the time the trace functions are set.
140  *  @param fnNumber Enum value indicating the ICU function being exited.
141  *  @param level    The current tracing level
142  *  @param fmt      A format string describing the tracing data that is supplied
143  *                  as variable args
144  *  @param args     The data being traced, passed as variable args.
145  *  @stable ICU 2.8
146  */
147typedef void U_CALLCONV
148UTraceData(const void *context, int32_t fnNumber, int32_t level,
149           const char *fmt, va_list args);
150
151/**
152  *  Set ICU Tracing functions.  Installs application-provided tracing
153  *  functions into ICU.  After doing this, subsequent ICU operations
154  *  will call back to the installed functions, providing a trace
155  *  of the use of ICU.  Passing a NULL pointer for a tracing function
156  *  is allowed, and inhibits tracing action at points where that function
157  *  would be called.
158  *  <p>
159  *  Tracing and Threads:  Tracing functions are global to a process, and
160  *  will be called in response to ICU operations performed by any
161  *  thread.  If tracing of an individual thread is desired, the
162  *  tracing functions must themselves filter by checking that the
163  *  current thread is the desired thread.
164  *
165  *  @param context an uninterpretted pointer.  Whatever is passed in
166  *                 here will in turn be passed to each of the tracing
167  *                 functions UTraceEntry, UTraceExit and UTraceData.
168  *                 ICU does not use or alter this pointer.
169  *  @param e       Callback function to be called on entry to a
170  *                 a traced ICU function.
171  *  @param x       Callback function to be called on exit from a
172  *                 traced ICU function.
173  *  @param d       Callback function to be called from within a
174  *                 traced ICU function, for the purpose of providing
175  *                 data to the trace.
176  *
177  *  @stable ICU 2.8
178  */
179U_STABLE void U_EXPORT2
180utrace_setFunctions(const void *context,
181                    UTraceEntry *e, UTraceExit *x, UTraceData *d);
182
183/**
184  * Get the currently installed ICU tracing functions.   Note that a null function
185  *   pointer will be returned if no trace function has been set.
186  *
187  * @param context  The currently installed tracing context.
188  * @param e        The currently installed UTraceEntry function.
189  * @param x        The currently installed UTraceExit function.
190  * @param d        The currently installed UTraceData function.
191  * @stable ICU 2.8
192  */
193U_STABLE void U_EXPORT2
194utrace_getFunctions(const void **context,
195                    UTraceEntry **e, UTraceExit **x, UTraceData **d);
196
197
198
199/*
200 *
201 * ICU trace format string syntax
202 *
203 * Format Strings are passed to UTraceData functions, and define the
204 * number and types of the trace data being passed on each call.
205 *
206 * The UTraceData function, which is supplied by the application,
207 * not by ICU, can either forward the trace data (passed via
208 * varargs) and the format string back to ICU for formatting into
209 * a displayable string, or it can interpret the format itself,
210 * and do as it wishes with the trace data.
211 *
212 *
213 * Goals for the format string
214 * - basic data output
215 * - easy to use for trace programmer
216 * - sufficient provision for data types for trace output readability
217 * - well-defined types and binary portable APIs
218 *
219 * Non-goals
220 * - printf compatibility
221 * - fancy formatting
222 * - argument reordering and other internationalization features
223 *
224 * ICU trace format strings contain plain text with argument inserts,
225 * much like standard printf format strings.
226 * Each insert begins with a '%', then optionally contains a 'v',
227 * then exactly one type character.
228 * Two '%' in a row represent a '%' instead of an insert.
229 * The trace format strings need not have \n at the end.
230 *
231 *
232 * Types
233 * -----
234 *
235 * Type characters:
236 * - c A char character in the default codepage.
237 * - s A NUL-terminated char * string in the default codepage.
238 * - S A UChar * string.  Requires two params, (ptr, length).  Length=-1 for nul term.
239 * - b A byte (8-bit integer).
240 * - h A 16-bit integer.  Also a 16 bit Unicode code unit.
241 * - d A 32-bit integer.  Also a 20 bit Unicode code point value.
242 * - l A 64-bit integer.
243 * - p A data pointer.
244 *
245 * Vectors
246 * -------
247 *
248 * If the 'v' is not specified, then one item of the specified type
249 * is passed in.
250 * If the 'v' (for "vector") is specified, then a vector of items of the
251 * specified type is passed in, via a pointer to the first item
252 * and an int32_t value for the length of the vector.
253 * Length==-1 means zero or NUL termination.  Works for vectors of all types.
254 *
255 * Note:  %vS is a vector of (UChar *) strings.  The strings must
256 *        be nul terminated as there is no way to provide a
257 *        separate length parameter for each string.  The length
258 *        parameter (required for all vectors) is the number of
259 *        strings, not the length of the strings.
260 *
261 * Examples
262 * --------
263 *
264 * These examples show the parameters that will be passed to an application's
265 *   UTraceData() function for various formats.
266 *
267 * - the precise formatting is up to the application!
268 * - the examples use type casts for arguments only to _show_ the types of
269 *   arguments without needing variable declarations in the examples;
270 *   the type casts will not be necessary in actual code
271 *
272 * UTraceDataFunc(context, fnNumber, level,
273 *              "There is a character %c in the string %s.",   // Format String
274 *              (char)c, (const char *)s);                     // varargs parameters
275 * ->   There is a character 0x42 'B' in the string "Bravo".
276 *
277 * UTraceDataFunc(context, fnNumber, level,
278 *              "Vector of bytes %vb vector of chars %vc",
279 *              (const uint8_t *)bytes, (int32_t)bytesLength,
280 *              (const char *)chars, (int32_t)charsLength);
281 * ->  Vector of bytes
282 *      42 63 64 3f [4]
283 *     vector of chars
284 *      "Bcd?"[4]
285 *
286 * UTraceDataFunc(context, fnNumber, level,
287 *              "An int32_t %d and a whole bunch of them %vd",
288 *              (int32_t)-5, (const int32_t *)ints, (int32_t)intsLength);
289 * ->   An int32_t 0xfffffffb and a whole bunch of them
290 *      fffffffb 00000005 0000010a [3]
291 *
292 */
293
294
295
296/**
297  *  Trace output Formatter.  An application's UTraceData tracing functions may call
298  *                 back to this function to format the trace output in a
299  *                 human readable form.  Note that a UTraceData function may choose
300  *                 to not format the data;  it could, for example, save it in
301  *                 in the raw form it was received (more compact), leaving
302  *                 formatting for a later trace analyis tool.
303  *  @param outBuf  pointer to a buffer to receive the formatted output.  Output
304  *                 will be nul terminated if there is space in the buffer -
305  *                 if the length of the requested output < the output buffer size.
306  *  @param capacity  Length of the output buffer.
307  *  @param indent  Number of spaces to indent the output.  Intended to allow
308  *                 data displayed from nested functions to be indented for readability.
309  *  @param fmt     Format specification for the data to output
310  *  @param args    Data to be formatted.
311  *  @return        Length of formatted output, including the terminating NUL.
312  *                 If buffer capacity is insufficient, the required capacity is returned.
313  *  @stable ICU 2.8
314  */
315U_STABLE int32_t U_EXPORT2
316utrace_vformat(char *outBuf, int32_t capacity,
317              int32_t indent, const char *fmt,  va_list args);
318
319/**
320  *  Trace output Formatter.  An application's UTraceData tracing functions may call
321  *                 this function to format any additional trace data, beyond that
322  *                 provided by default, in human readable form with the same
323  *                 formatting conventions used by utrace_vformat().
324  *  @param outBuf  pointer to a buffer to receive the formatted output.  Output
325  *                 will be nul terminated if there is space in the buffer -
326  *                 if the length of the requested output < the output buffer size.
327  *  @param capacity  Length of the output buffer.
328  *  @param indent  Number of spaces to indent the output.  Intended to allow
329  *                 data displayed from nested functions to be indented for readability.
330  *  @param fmt     Format specification for the data to output
331  *  @param ...     Data to be formatted.
332  *  @return        Length of formatted output, including the terminating NUL.
333  *                 If buffer capacity is insufficient, the required capacity is returned.
334  *  @stable ICU 2.8
335  */
336U_STABLE int32_t U_EXPORT2
337utrace_format(char *outBuf, int32_t capacity,
338              int32_t indent, const char *fmt,  ...);
339
340
341
342/* Trace function numbers --------------------------------------------------- */
343
344/**
345 * Get the name of a function from its trace function number.
346 *
347 * @param fnNumber The trace number for an ICU function.
348 * @return The name string for the function.
349 *
350 * @see UTraceFunctionNumber
351 * @stable ICU 2.8
352 */
353U_STABLE const char * U_EXPORT2
354utrace_functionName(int32_t fnNumber);
355
356U_CDECL_END
357
358#endif
359